Sorrento Therapeutics (NSDQ:SRNE) subsidiary Scilex Pharmaceuticals touted data today from a head-to-head clinical adhesion study of its ZTlido lidocaine patch, comparing it to the EU reference product, Versatis.

ZTlido is a lidocaine patch in development for the treatment of post-herpetic neuralgia – a severe neuropathic pain condition that affects elderly people and patients who have had a Shingles infection, HIV/AIDS or cancer. The anhydrous patch contains just 36 milligrams of lidocaine, compared to Lidoderm and Versatis which each have 700 milligrams of the painkiller.

The comparative study was designed to support ZTlido’s market authorization application in the EU. The study’s results complement a previous clinical adhesion study performed for the product’s new drug application submission in the U.S.

Scilex said it plans to resubmit the patch’s NDA and MAA in the 2nd half of this year.

The product was designed to adhere better to the skin compared to the U.S. and EU reference products, Lidoderm and Versatis, since adhesion is crucial to maintain safety and efficacy of a medicated plaster product, according to Scilex.

The study’s primary endpoint was to demonstrate statistically significant non-inferior mean adhesion at each of the pre-determined time points. In 44 healthy volunteers, the researchers assessed adhesion at 0, 3, 6, 9 and 12 hours. Adhesion was scored using an EMA scale ranging from 6, being greater than 95% adhesion, and a score of 0, meaning significant adhesion failure.

ZTlido had superior adhesion compared to Versatis, with mean adhesion scores of 5.35 and 3.59 respectively. At the end of the 12-hour time period, ZTlido had a mean adhesion score of 5.006 and Versatis had a mean adhesion score of 2.268.

Two participants had complete detachment with Versatis, but there were no detachments in the ZTlido group. There was also no statistically significant difference in the mean dermal irritation scores between the 2 products.

“We are pleased to report our noteworthy data. We believe that the ability of ZTlido to outperform Versatis in this head to head study will translate into better patient compliance and provide us with an important clinical advantage.  I look forward to moving ZTlido closer to commercialization in the U.S. and the EU,” Scilex president Anthony Mack said in prepared remarks.

“Sorrento continues to be pleased with the outcome of this data and the results of the recently released pivotal PK studies,” Sorrento president & CEO Henry Ji added.  “The US and European Union markets represent attractive market opportunities for ZTlido and we will continue to support product development efforts for this groundbreaking asset.”